Some particularly eggcellent news has arrived just in time for Easter at Auckland Zoo, New Zealand, where keepers are showing off four tiny Galápagos tortoises who have hatched at the zoo. These bitesize babies (compared to their massive parents) are just seven weeks old, born from parents Chippie and Smiley, 50 and 49 years old respectively. The new arrivals are no doubt a great source of pride for Auckland Zoo, as they represent a record number of baby Galápagos tortoises to have hatched and survived from a single clutch raised within the Australasian zoo population.
The four babies are reported on Instagram to weigh around 74-88 grams (2.6 to 3.1 ounces) each – featherlight compared to the adult weight they will one day reach of around 227 kilograms (500 pounds) for males or 113 kilograms (250 pounds) for females. Thanks to the ingenuity that is the inner workings of a tortoise’s shell, their enormous weight is down to the animal’s soft tissues rather than its massive shell. Tortoise and turtle shells might look bulky, but thanks to their unique structure and the fact that their lungs sit at the top of the carapace (dome on top), turtles and tortoises can all float in water.
“This is a huge milestone for us and a credit to our incredible ectotherm team for the expert care and husbandry they provide for this species,” wrote Auckland Zoo in an Instagram post. “Excitingly, this has meant breaking the record for the most hatchlings to come from a single clutch within the small Australasian zoo population of this endangered reptile.”
There were once 15 species of giant tortoise endemic to the Galápagos Islands, but when the region was colonized in the late 1800s the whalers and pirates brought with them a cast of invasive pests that outcompeted the tortoises for food and ate their hatchlings. With the support of conservationists, there is now an estimated population of 6,700 giant tortoises roaming free on the Galápagos. Captive rearing of tortoises hopes to maintain the genetic diversity of the remaining species of Galápagos tortoises, but rearing them is no easy task.
“These are famously challenging tortoises to rear,” said Auckland Zoo’s Ectotherm team leader Don. “Success will only truly come when these hatchlings reach adulthood in 20-40 years - it’s a long game!”
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